Updates On Smoking Cessation
- 1. Successful SMOKING CESSATION Dr. Sallehudin Bin Abu Bakar MD (M’sia); MPH (Philippines); M.Epid.(Johns Hopkins)
- 2. The integrated approach to successful smoking cessation Professional involvement Behavioural support Proven pharmacotherapy
- 4. Non-Physiological Reasons for Smoking Peer pressure Mass media Pleasure and relaxation Nature of work Improved thinking and performance Relief from negative moods (anxiety, stress, anger, irritability and depressed mood) Weight control
- 5. Physiological Reasons for Smoking Physical dependence on nicotine Relief from withdrawal symptoms
- 6. Effects of Nicotine Withdrawal When nicotine levels drop, most smokers report physiological withdrawal symptoms such as : Anxiety Irritability Restlessness Difficulty in concentrating Stomach problems Craving Drowsiness
- 7. Nicotine Circulation in the Body When the smoker inhales Nicotine first enters the lungs Quickly enter the pulmonary circulation and is pumped into the heart The heart pumps the nicotine-laden blood throughout the body Reaches the brain only 7 to 10 secs after inhalation
- 8. Effects on the Nervous System Nicotine acts on the central and autonomic nervous systems by stimulating the brain’s nicotinic receptors Changes in mood, learning, concentration, alertness and performance Physical changes such as up-regulation of the brain (increase in no. of nicotine receptors) Change in metabolism and energy utilisation in the brain, similar to other addictive drugs EEG changes Alteration of the endocrine system functioning
- 9. Effects on the Nervous System These changes in the physical make-up and functioning of the brain and nervous system may contribute to the development of : Nicotine Tolerance Physical Dependence
- 10. Health Benefits Within days of quitting, carbon monoxide from smoking begins to leave the body Within weeks, ex-smokers begin to breathe easier and enjoy improved senses of taste and smell One year after quitting, risk of death from coronary heart disease decrease by 50% and continues to decline with time Risk of stroke and lung cancer are also reduced significantly over time
- 11. Health Benefit Overall, fifteen years after quitting, the overall risk of death is about the same as for those who have never smoked.
- 12. Health Benefits One-fourth of smokers die early because of smoking A 25 year-old heavy smoker’s life expectancy may be shortened by more than 25% compared to a non-smoker
- 13. Smoking Finances Assuming a smoker spends RM8.00 a day on cigarettes (1 pack of 20’s), quitting will save RM2,920.00 a year.
- 14. The Cessation Reality 74% of current smokers want to quit Only 25% of those who manage to quit remain abstinent for longer than 1 year 1.3 million (6.5%) experience long term success
- 15. Obstacles to Cessation Nicotine addiction Stress / anxiety Fear of gaining weight Peer pressure Many have tried and failed!
- 17. Addiction Triangle Physical (Neurochemistry) Emotional (Psychological) Habitual (Routine) FACTORS AFFECTING ADDICTION
- 18. Nicotine Addiction Brain disease Compulsive need for and use of a habit-forming substance characterised by tolerance and by well-defined physiological symptoms upon withdrawal Cigarette Smoking Is An Addiction! Not Just A Bad Habit.
- 19. Dependence Occurs when body becomes accustomed to the presence of nicotine and is altered in such a way that it needs nicotine in order to function normally To feel stabilised, heavy smokers need to maintain a high level of nicotine in their brains and will unconsciously regulate their puff rate until this requirement is met Addiction and Dependence are used interchangeably despite that “dependence” does not incorporate the compulsive use aspect
- 20. Two Types of Addiction Interplay of the two types of addiction that make smoking so addicting and so difficult to give up Ingestive addiction Process addiction
- 21. Ingestive Addiction Excessively and compulsively taking into the body artificially refined or produced mood-altering substances such as specific foods, drugs, gases, alcohol or tobacco
- 22. Process Addiction “ Hooked” on a set of neutral actions, interactions, or behaviours that become overused to the point where they lose their original value, meaning and purpose Highly addictive - gambling, working, exercising, spending money, or eating
- 23. Physiology of Nicotine Addiction Cigarette smoking is being reinforced by both positive and negative processes Nicotine affects both reward and withdrawal pathways Dopaminergic effects in nucleus accumbens involved in reward Noradrenergic effects in locus ceruleus involved in withdrawal
- 24. Anatomy of Reward and Withdrawal Mesolimbic Dopamine System Nucleus Accumbens Prefrontal Cortex Locus Ceruleus
- 25. Physiology of Addiction Dopaminergic pathway Also known as the reward pathway or mesolimbic pathway Between the ventral tegmental area to the nucleus accumbens These contain high density of nicotinic receptors Responsible for motivational behaviour - the need to reproduce and survive Produces pleasurable effects and positive reinforcement
- 26. The Reward Pathway Dopamine surge in the nucleus accumbens is thought to produce the same positive motivational state associated with food and sex
- 27. The Reward Pathway While all highly addictive drugs activate the mesolimbic pathway, nicotine is a particularly reinforcing drug because it is inhaled and nicotine levels in the brain rise very rapidly (within 10 secs), producing a more powerful effect than drugs taken orally
- 28. Physiology of Nicotine Addiction The combination of heightened arousal with pleasure trigger creates a sense of cyclical satisfaction Each time a smoker smoke, these states are being reinforced. Reinforcing message “You will only continue to feel well if you continue smoking” is the foundation of lifelong nicotine addiction.
- 29. Smoker’s Withdrawal Withdrawal is mediated by norepinephrine in the locus ceruleus Approximately 80% of individuals who quit smoking experience physiological withdrawal effects such as Irritability - Increased taste of sweets Difficulty concentrating - Weight gain Restlessness - Gastrointestinal problems Cravings - constipation Anxiety - Increased hunger Drowsiness
- 30. Smoker’s Withdrawal Withdrawal symptoms begin 6 to 12 hours after cessation Most intense within the first 3 days May last from a few days to many months About 25% of those who quit smoking relapse within 48 hours 50% relapse within the first 7 days 75% relapsed in 1 year
- 31. The Reality of Nicotine Addiction The smoker experience positive reinforcement every time he lights a cigarette and stimulates the reward pathway He also receives negative reinforcement through withdrawal symptoms and must light another cigarette to relieve them
- 33. Healthcare Provider Strategies The Agency for Health Care Policy and Research (AHCPR) Clinical Practice Guidelines : 1. Every person who smokes should be offered smoking cessation treatment at every visit 2. Ask and record the tobacco use status of every patient 3. Clinician intervention, even as brief as 3 mins, is effective 4. The more intensive the treatment, the more effective it is in producing long-term abstinence from tobacco 5. Nicotine-replacement therapy, social support, and skills training are effective components of smoking cessation treatment
- 34. “ 5 A’s” for Smoking Cessation ASK 1. Systematically identify ALL tobacco users at every visit ADVISE 2. Strongly urge all smokers to quit ASSES 3. Asses smokers willingness to make a quit attempt ASSIST 4. Aid the patient with a quit plan ARRANGE 5. Follow-up to monitor progress
- 35. Assisting Patient in Quitting Help the patient set a quit date and prepare for quitting Encourage pharmacotherapy except in special circumstances Give key advice on successful quitting Provide supplementary materials
- 36. A Quit Plan Setting a quit date - within 2 weeks of the decision to quit Should inform family, friends, co-workers of quitting and request for understanding and support Remove cigarettes from the environment and, prior to quitting, avoid smoking in places where they spend a lot of time, e.g. the car Review previous quit attempts to determine what was helpful and what led to relapse
- 37. Key Advice on Successful Quitting Abstinence - “Not even a single puff after quit date” Alcohol - associated with relapse Other smokers in the household- developing specific plans to deal with their abstinence in a household where others still smoke
- 38. Patient Types 5 Stages of smoking cessation readiness : Pre-contemplation Not seriously considering quitting Clinicians should put their effort towards motivating the patients to consider quitting Contemplation Seriously considering quitting Clinician should help to develop a quit plan
- 39. Patient Types Action Actively trying to quit or has recently quit Clinicians should advise smokers on coping strategies to reduce withdrawal symptoms and at the same time discuss specific treatment options Maintenance Has quit and is attempting to avoid relapse Clinicians should follow-up and advise them on relapse prevention strategies
- 40. Patient Types Relapse Very common and most difficult Help patients realise that relapse is part of cessation process not a failure Able to learn from the causes of relapse Develop a more intensive treatment on the next attempt
- 42. Intervention Strategies Non-pharmacological Self-help Behavioural Group support Hypnosis Acupuncture Pharmacological Nicotine replacement Bupropion Verinicline
- 43. Management Researchers and clinicians view nicotine addiction as a brain disease embedded in a social context Effective treatment should incorporate both : Behavioural Therapy Medication
- 45. Self-help Programmes Smoking Cessation Clinics Counselling support Behavioural programmes If the above programmes are inadequate, then pharmacological therapies are sought
- 46. Behavioural Programmes Self-management strategies Aversion conditioning techniques Relapse-prevention methods Nicotine fading
- 47. Self-Management Strategies Most commonly used Make smokers more aware of their smoking patterns and cues Self-monitoring Record when, where, and why they smoke Promote a behavioural change and design a treatment plan Stimulus control (Cue extinction) Done before quitting to reduce the strength of the smoking cue Avoiding dominant cues (talking on the phone, finishing a meal
- 48. Aversion Conditioning Techniques Should only be administered by trained smoking cessation specialists Used to decrease a smoker’s urge to smoke before quit dates or upon relapse Techniques include rapid smoking and satiation Rapid smoking : Smokers puff cigarettes every 6 to 8 seconds until the cigarette is gone or nausea occurs Satiation : Smokers double or triple their daily cigarette consumption for brief periods of time
- 49. Relapse-Prevention Methods Designed to prevent smokers from returning to smoking behaviour Avoidance : Minimising exposure to temptations, e.g. stress, other smokers Coping Strategies : Techniques such as deep breathing or use of relaxation tapes, to deal with withdrawal symptoms Contingency management : Rewards and punishments
- 50. Nicotine Fading Gradual reduction of nicotine intake : Tapering the number of cigarettes smoked Switching to brands containing less nicotine Disadvantage : Smokers can compensate by inhaling more deeply and longer Further reinforce each episode of smoking Results are inconsistent and thus not recommended for routine use
- 51. Group Smoking Cessation Programmes Most smokers are unwilling to attend such programmes Option for smokers who have failed to respond to less intensive cessation methods Done in small group with multiple sessions Incorporate various types of behavioural approaches
- 52. Hypnosis and Acupuncture Appeal to smokers who want rapid cessation with little effort Claims to have high cure rates up to 95% No clinical data to support efficacy of these methods
- 54. Nicotine Replacement Therapies Gum Transdermal patches Nasal Spray Oral Inhaler Lozenges
- 55. Nicotine Gum Administered on an as-desired basis Most people chew 8 to 15 pieces a day; Each piece is chewed for 20 to 30 mins Approximately 50% of nicotine is released Providing 8 to 15mg of nicotine per day from the 2-mg form and 16 to 30mg from 4-mg form Approx. one-third or one-half of the usual daily intake of a person who smokes 30 cigarettes daily Recommended use for 4 to 6 months and patients should be encouraged to wean from nicotine gum, but the optimal duration of use is unknown
- 56. Efficacy of Nicotine Gum Successful only accompanied by intensive behavioural programmes Acidic drinks, such as coffee or soda, decrease acidity of saliva and may interfere with the effects of nicotine gum One should never smoke and chew
- 57. Safety and Adverse Effects of Nicotine Gum Flatulence Indigestion Nausea Unpleasant taste Hiccups Sore mouth, throat and jaw
- 58. Nicotine Patches Delivering a steady amount of nicotine to the body right through the skin (usually on an arm, abdomen) Easy to use Once a day (changing the location each time)
- 59. Start with TTS 30 or TTS 20 depending on no. of cigarettes smoked/day Those smoking >20 sticks/day start with TTS 30 Those smoking <20 sticks/day start with TTS 20 Use 30, 20 and 10 cm 2 to allow gradual withdrawal Use over 3-4 weeks treatment Treatment > 3 months and doses > 30 cm 2 have not been evaluated Nicotine Patches
- 60. Safety and Adverse Effects of Nicotine Patches Skin irritation at the patch site Insomnia Headache Cold and flu-like symptoms Nausea Myalgia Dizziness Less common : Sleep disturbance, GI side effects - diarrhoea, upset stomach
- 61. Safety of Replacement Therapies NRTs should be used with extra caution in patients with cardiovascular disease Smoking while using patch or gum therapy may increase the risk of cardiovascular and toxic effects of nicotine Patients should stop smoking completely when starting treatment In addition, many smokers see such therapy as simply prolonging their dependence or fear becoming dependent on the replacement itself
- 62. Works on the biology of nicotine addiction By enhancing dopamine levels in the reward pathway Affect noradrenergic neurons in the locus ceruleus to reduce craving and withdrawal symptoms Bupropion
- 63. Dosage & Administration for Bupropion Start with 150mg/day for the first 3 days Follow by a dose increase to 300mg/day given as 150mg b.d. (at 8-hourly interval) Maximum dose : 300 mg/day Doses above 300mg/day should not be used due to dose-dependent risk of seizures
- 64. Dosage & Administration Patients should start taking bupropion BEFORE they quit smoking They should set a “target quit date” during the 2nd week of treatment with bupropion as it takes about 1 week to reach steady-state blood levels Treatment with bupropion should be continued for 7-12 weeks Dose tapering is not necessary when discontinuing bupropion Important that patients continue to receive counselling and support throughout treatment with bupropion, and for a period of time thereafter
- 65. Individualization of Therapy Need for education/counseling/support Discontinue if patient has not made significant progress toward abstinence by the seventh week of therapy If unsuccessful, re-evaluate later for retrial of therapy Bupropion should be used as a part of a comprehensive smoking cessation treatment program
- 66. Bupropion in Clinical Practice Bupropion is indicated for the treatment of nicotine dependence as an aid to smoking cessation in subjects aged 18 years and over. Adult smokers who are motivated to stop could benefit from treatment with bupropion. For the majority of patients, the recommended dosage is 150mg once daily for 3 days, increasing to 150mg twice daily.
- 67. Combination Therapy for the Heavily Addicted Smoker—Mayo Clinic Style Nicotine patch Strongest dose, can use more than one Shorter acting nicotine replacement Bupropion SR
- 68. Varenicline Tartrate (Champix ® ) Indicated for smoking cessation in adults Oral administration (tablet) Non-nicotine a partial agonist selective for the α 4β2 nicotinic acetylcholine receptor Dual action with dual benefits Partial agonist activity: Reduces craving and withdrawal symptoms Antagonist activity: Produces a reduction of the rewarding and reinforcing effects of smoking () 1. Champix Prescribing Information
- 69. Champix ® (Varenicline): A Highly Selective 4 2 Receptor Partial Agonist 1. Coe JW et al. Presented at the 11th Annual Meeting and 7th European Conference of the Society for Research on Nicotine and Tobacco. 2005. Prague, Czech Republic. 2. Picciotto MR et al. Nicotine Tob Res. 1999; Suppl 2:S121-S125. Binding of nicotine at the 4 2 nicotinic receptor in the VTA is believed to cause release of dopamine at the nAcc Champix is an 4 2 nicotinic receptor partial agonist, a compound with dual agonist and antagonist activities. This is believed to result in both a lesser amount of dopamine release from the VTA at the nAcc as well as the prevention of nicotine binding at the 4 2 receptors. Nicotine Champix
- 70. Varenicline: 4 2 nAChR Partial Agonists 4 2 nAChR Dual action of a partial agonist Agonist Response 100% Smoking No Partial Ag No Smoking Partial Ag Smoking + Partial Ag Antagonist Partial Agonist Nicotine Part Ag Part ag Nicotine 50% Potential to block reinforcing effects when smoking 50% Potential to relieve craving and withdrawal when quitting
- 71. Varenicline on nicotinic receptors and dopamine release
- 72. Varenicline (Champix ® ): Dosage Treatment period is 12 weeks An additional course of 12 weeks of treatment may be considered for patients who have successfully quit at end of 12 weeks Varenicline is supplied for oral administration in 2 strengths: 0.5 and 1.0 mg; titration is as below: 1. Champix Prescribing Information Days 1 – 3: 0.5 mg once daily Days 4 – 7: 0.5 mg twice daily Day 8 – End of treatment: 1 mg twice daily
- 73. Pharmacokinetics of Varenicline Half-life ~24 hours Cmax within 3 to 4 hours Steady state reached within 4 days Oral bioavailability unaffected by food 92% of drug is excreted unchanged No inhibition of cytochrome P450 enzymes No clinically meaningful drug interactions identified No dose restrictions in patients with hepatic insufficiency Dose adjustment required for severe renal impairment, may be considered for moderate renal impairment No dosage adjustment is necessary for elderly patients absent renal impairment 1. Champix Prescribing Information
- 74. Adverse Effects During clinical trials, approximately 4000 individuals were exposed to varenicline Most frequently reported AEs (≥10%) associated with varenicline 1 mg vs placebo were: Nausea Abnormal dreams Insomnia Headache The percentage of participants who discontinued treatment due to adverse events receiving varenicline treatment was comparable; 11.4% vs 9.7% 1. Varenicline Prescribing Information
- 75. Contraindications & Interactions Contraindications: hypersensitivity to the active substance or to any of the excipients No clinically meaningful drug interactions have been identified with varenicline 1. Champix Prescribing Information
- 76. Precautions There are no adequate data from the use of varenicline in pregnant women Varenicline should not be used during pregnancy It is unknown whether varenicline is excreted in human breast milk Animal studies suggest varenicline is excreted in breast milk A decision whether to discontinue varenicline or discontinue breastfeeding should consider the benefits of breastfeeding to the child and varenicline to the woman Varenicline may have minor or moderate influence on the ability to drive and use machines Patients are advised not to engage in potentially hazardous activities until it is known whether their ability to perform these activities is affected 1. Champix Prescribing Information
- 77. Dose Adjustment in Special Populations Patients with hepatic impairment No dosage adjustment necessary Patients with renal insufficiency No dosage adjustment necessary for patients with mild to moderate renal impairment For patients with moderate renal impairment who experience adverse events that are not tolerable, dosing may be reduced to 1 mg once daily For patients with severe renal impairment, the recommended dose is 1 mg/d. Dosing should begin at 0.5 mg once daily for the first 3 days then increase to 1 mg once daily. In patients with end-stage renal disease, treatment is not recommended 1. Champix Prescribing Information
- 78. Comparative Daily Costs of Pharmacotherapy Cost per day, in U.S. dollars $6.07 $5.81 $5.73 $5.26 $3.91 $3.67 $4.22 $4.26
- 79. New Medications in the Pipeline Rimonabant Cannabinoid receptor inhibitor Blocks reinforcing effects of nicotine Also suppresses appetite In phase III trials Not approved for smoking cessation by FDA Nicotine Vaccine Produces antibodies to nicotine Reduces nicotine levels in animals CYP246 Inhibitors CYP246 is a hepatic enzyme that metabolizes nicotine Higher blood nicotine levels per cigarette smoked Could also increase potency of NRT
- 80. Smoking Cessation: A Very Powerful Intervention… Critchley JA, Capewell S. JAMA ;2003;290:86-97 Intervention Reduction in Mortality Smoking Cessation 36% Statin Therapy 29% Beta-Blockers 23% ACE Inhibitors 23% Aspirin 15%
- 81. Effects of Clinician Interventions Estimated abstinence at 5+ months 1.0 1.1 (0.9,1.3) 1.7 (1.3,2.1) 2.2 (1.5,3.2) n = 29 studies Type of clinician Fiore et al. Treating Tobacco Use and Dependence. Clinical Practice Guideline. USDHHS, PHS, 2000. Compared to smokers who receive no assistance from a clinician, smokers who receive such assistance are 1.7 – 2.2 times as likely to quit successfully for 5 or more months.
- 82. Power of Intervention ⅓ to ½ of the 44.5 million smokers will die from the habit. Of the 31 million who want to quit, 10 to 15.5 million will die from smoking. Increasing the 2.5% cessation rate to 10% would save 1.2 million additional lives. If cessation rates rose to 15%, 1.9 million additional lives would be saved. No other health intervention could make such a difference!
Editor's Notes
- #3: Notes: GlaxoSmithKline offers an integrated approach to successful quitting: endorsement and promotion of healthcare professional involvement – imparting knowledge, confidence, motivation and commitment to smokers who want to quit advanced pharmacotherapies help smokers to combat cravings behavioral support plans help to maintain motivation and ensure the individual is well informed on all aspects of smoking cessation, providing the best opportunity for success.
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- #68: Expressing empathy – reflective listening ala Rogers, ambivalence is the normal human condition
- #69: Key Point Varenicline, the active ingredient in Champix (as the tartrate salt), is a partial agonist selective for α4β2 nicotinic acetylcholine receptor subtypes. Background Varenicline, the active ingredient in Champix (as the tartrate salt), is a partial agonist with high selectivity and affinity for α4β2 nicotinic acetylcholine receptor subtypes. Varenicline tartrate is a white to off-white to slightly yellow powder that is highly soluble in water, with a molecular formula of C 13 H 13 N 3 • C 4 H 6 O 6 . Reference 1. Chantix package insert. Pfizer Labs, a division of Pfizer Inc., New York, NY, USA PI/p. 5/¶1,2
- #70: Key Point Champix ™ (varenicline) was deliberately designed for the 4 2 receptor, as an 4 2 nicotinic receptor partial agonist (with dual agonist and antagonist properties) and physically prevents nicotine from binding as an aid in smoking cessation. Background The initial view of the mesolimbic system identifies the VTA where the 4 2 receptors predominate, as well as the nAcc. The release of dopamine at the nAcc from the axons of the dopamine cells of the VTA is believed to produce a reward response. When nicotine binds at the 4 2 nicotinic receptor in the VTA, it is believed to cause release of dopamine at the nAcc. Champix ™ (varenicline) was deliberately designed for the 4 2 receptor, as an 4 2 nicotinic receptor partial agonist (with dual agonist and antagonist properties) and physically prevents nicotine from binding and releases intrinsically less dopamine at the nAcc. References Coe JW, Brooks PR, Wirtz MC, et al. Varenicline (CP-526, 555): A novel, potent, and selective nicotinic receptor partial agonist for the treatment of smoking cessation: Rationale, discovery, and mode of action. Presented at the 11th Annual Meeting and 7th European Conference of the Society for Research on Nicotine and Tobacco, March 20–23, 2005, Prague, Czech Republic. Picciotto MR, Zoli M, Changeux J. Use of knock-out mice to determine the molecular basis for the actions of nicotine. Nicotine Tob Res. 1999; Suppl 2:S121-S125.
- #71: With this compound you can see that nicotine binds to alpha-4 beta-2 nicotinic receptors in the VTA of the brain causing an agonist or 100% response. In theory Chantix will, by being a partial agonist, bind and give a partial agonist response, which we refer to as 40% in terms of dopamine release. By occupying the receptor, you can see that nicotine is unable to attach to the receptor once Chantix is on board. Therefore by smoking you receive no additional reward, but you don’t also have the low levels of dopamine that would lead to a relapse to smoking. These were the intended and hopefully achievable objectives of the program at the outset in 1993. A partial agonist would be a novel objective for Pfizer, and the industry.
- #73: Key Point Varenicline is indicated for smoking cessation in adults. Background Varenicline is indicated for smoking cessation in adults. When prescribing varenicline, physicians also should provide patients with advice and support concerning their attempt at quitting smoking, as smoking cessation therapies appear to be more likely to be successful in conjunction with behavioral interventions. Patients must choose a date to quit smoking and initiate varenicline treatment 1 – 2 weeks before this date. Varenicline should be taken with a full glass of water, with or without food, with titration according to the following schedule: an initial dose of one 0.5 mg tablet once daily for the first 3 days, then one 0.5 mg taken in the morning and one 0.5 mg tablet taken in the evening for the next four days up to day 7. After the first 7 days, the dose should be increased to one 1.0 mg tablet in the morning and one 1.0 mg tablet in the evening. Patients who cannot tolerate varenicline may have the dose lowered temporarily or permanently to 0.5 mg BID. Reference 1. Champix Summary of Product Characteristics. Pfizer Ltd, Sandwich, UK. 2006. Champix Summary of Product /p 2/¶6,7,9-11;Table Champix Summary of Product /p 2/¶6,7,9-11;Table
- #74: Key Point Among varenicline’s pharmacokinetic properties, clinically relevant features include: maximum plasma concentrations within 3 – 4 hours after administration, steady-state conditions within 4 days, bioavailability unaffected by food or time-of-day dosing, varenicline undergoes minimal metabolism, its elimination half-life is approximately 24 hours, and it exhibits linear kinetics. PI/p. 6/¶2,3,4; p. 7/¶6 PI/p. 6/¶2,3,4; p. 7/¶6
- #75: Key Point The percentage of participants who discontinued treatment due to AEs receiving varenicline treatment was 11.4% vs 9.7% receiving placebo. More study participants who received varenicline treatment experienced nausea (28.6%) compared with those who received placebo. Background Approximately 4000 individuals were exposed to varenicline during clinical trials for up to 1 year (average 84 days). In placebo-controlled trials, the treatment discontinuation rate due to AEs was comparable between treatment groups: 11.4% in patients who received varenicline 1.0 mg twice daily compared with 9.7% in those who received placebo. Reference 1. Varenicline Summary of Product Characteristics. Pfizer Ltd, Sandwich, UK. 2006. Varenicline Summary of Product doc/p.5/¶3,4,5 Varenicline Summary of Product doc/p.5/¶3,4,5 Varenicline Summary of Product doc/p.5 and 6 Table
- #76: Key Point Varenicline has no meaningful drug interactions. Background Hypersensitivity to the active substance or to any of the excipients is the only contraindication to the use of varenicline. Special warnings and precautions include the independent effects of smoking cessation, with or without varenicline therapy. These effects involve the physiological changes resulting from smoking cessation, which may alter the pharmacokinetics or pharmacodynamics of some medicinal products and necessitate dosage adjustment. Further, smoking cessation has been associated with exacerbation of underlying psychiatric illness, so care should be taken with patients with a history of psychiatric illness. Discontinuation of varenicline was associated with an increased in irritability, urge to smoke, depression, and/or insomnia in up to 3% of patients. Patients should therefore be informed accordingly, and the need for dose tapering should be considered by the prescriber. Drug interaction studies have included combinations of varenicline and metformin, cimetidine, digoxin, and warfarin, and have identified no clinically meaningful pharmacokinetic drug–drug interactions. In addition, varenicline has been evaluated with concurrent use with other therapies for smoking cessation. Varenicline did not alter the steady-state pharmacokinetics of bupropion, though there was a statistically significant increase in average systolic blood pressure (mean 2.6 mmHg) when varenicline and transdermal NRT were coadministered for 12 days. The incidence of nausea, headache, vomiting, dizziness, dyspepsia, and fatigue was greater for the combination of varenicline and NRT than for NRT monotherapy. Reference 1. Champix Summary of Product Characteristics. Pfizer Ltd, Sandwich, UK. 2006 . Champix Summary of Product /p 3/ ¶8-12; p 4/¶1,10,11 Champix Summary of Product /p 3/ ¶8-12; p 4/¶1,10,11
- #77: Key Point As data are currently inadequate, varenicline should not be used during pregnancy. Benefits to both child and woman should be taken into account when deciding whether a patient should breastfeed or take varenicline. Potentially hazardous activities should be avoided until it is know whether use of varenicline will affect the ability to perform these activities. Background There are no adequate data from the use of varenicline in pregnant women, but studies in animals have shown reproductive toxicity. Although the potential risk for humans is unknown, varenicline should not be used during pregnancy. Similarly, animal studies suggest that varenicline is excreted in breast milk, but it is unknown whether this occurs in humans. The decision to discontinue breastfeeding or discontinue varenicline therapy should therefore take into account the benefits of breastfeeding to the child and varenicline therapy to the woman. Varenicline may have minor or moderate influence on the ability to drive and use machines because dizziness and somnolence may occur. Patients are advised not to engage in potentially hazardous activities until it is known whether their ability to perform these activities is affected while taking varenicline. Reference 1. Champix Summary of Product Characteristics. Pfizer Ltd, Sandwich, UK. 2006. Champix Summary of Product /p 4/ ¶14-15; p 5/¶ 1 Champix Summary of Product /p 4/ ¶14-15; p 5/¶ 1
- #79: This slide presents the approximate daily costs of treatment for the various pharmacotherapies for cessation. These are estimates* based on the recommended initial dosing for each agent. Costs can vary considerably depending on the patient’s level of smoking, degree of nicotine dependence, product selection (trade versus generic), and need for additional doses of short-acting NRT (gum, lozenge, nasal spray, or oral inhaler). As a comparison, the cost for one pack of cigarettes (national average, approximately $4.26) is shown (Campaign for Tobacco-Free Kids, 2006). In general, the daily cost of pharmacotherapy approximates the cost of one pack of cigarettes. For more exact estimates, refer to the Pharmacologic Product Guide . *Cost calculated using the most expensive average wholesale price for each agent (Drug Topics Redbook, 2006). Campaign for Tobacco-Free Kids. (2006). “State Cigarette Excise Tax Rates & Rankings.” Retrieved December 31, 2006 , from http://www.tobaccofreekids.org/research/factsheets/pdf/0097.pdf. Drug Topics Redbook. (2006, December). Montvale, NJ: Medical Economics Company, Inc. Slide is used with permission, Rx for Change: Clinician-Assisted Tobacco Cessation. Copyright © 1999-2007 The Regents of the University of California, University of Southern California, and Western University of Health Sciences. All rights reserved.
- #82: Decades of research tell us that clinicians can have an important impact on their patients’ likelihood of achieving cessation. A meta-analysis of 29 studies determined that patients who received a tobacco cessation intervention from a nonphysician clinician or a physician clinician were 1.7 and 2.2 times as likely to quit (at 5 or more months postcessation), respectively, compared with patients who did not receive such an intervention (Fiore et al., 2000). Self-help materials were only slightly better than no clinician. Fiore MC, Bailey WC, Cohen SJ, et al. (2000). Treating Tobacco Use and Dependence. Clinical Practice Guideline . Rockville, MD: U.S. Department of Health and Human Services, Public Health Service. Slide is used with permission, Rx for Change: Clinician-Assisted Tobacco Cessation. Copyright © 1999-2007 The Regents of the University of California, University of Southern California, and Western University of Health Sciences. All rights reserved.